This specification relates to conversion of input strings.
Conventional text is associated with a particular form, for example, a particular writing system and a particular natural language. A writing system can be used to represent one or multiple languages. For example, a Latin writing system (represented using Roman characters) can be used for the natural language English as well as for the natural language Chinese, e.g., as used in Romanized Chinese (e.g., Pinyin). Similarly, multiple writing system can be used to represent the same language. For example, Hanzi and Pinyin writing systems can be used to represent Chinese. Converting an input string between forms (e.g., from one writing system to another or from one natural language to another) can involve translation or transliteration of the input string.